Miiri, Elven Battlecaller

+3: Each creature you control gets +1/+2 and trample until end of turn.
-2: Target creature gets +X/+X and trample until end of turn, where X is the number of creatures you control.
-8: Target opponent gains an emblem with "Whenever a creature attacks you, it gets +6/+6 and trample until end of turn."